A related commentary discusses this research, congratulating the investigators for choosing a randomised screening design for this study rather than adding to the many uncontrolled phase 2 trials. This design has been proposed to identify potentially active new combinations or novel treatments to be taken forward into a phase 3 trial. It notes that, nevertheless, there are limitations of such a design. Seamless phase 2–3 designs with a landmark analysis for the phase 2 portion of the trial, and, if promising, an immediate subsequent transformation into a full phase 3 comparative trial might be another option. The screening design might also be appropriate to evaluate more than one novel compound or combination against a common control group.